| 摘要 |
The lenses of this invention have an optical axis that is deviated away from the line of sight, in a direction generally opposite the inward tilt of the lateral wrap and/or the incline of pantoscopic tilt, to offset the tilt induced prism. Low power may be introduced into the lenses to decrease their taper, further offset the tilt induced prism and astigmatism (particularly i n peripheral fields of view), lessen weight, provide better physical stability , and allow more uniform light transmission than plano lenses. The lenses may be cut from lens blanks in which the A line of the lens is at a non-zero angle to an equator of the lens, and the optical center of the lens may be horizontal ly and vertically displaced from the geometric center of the lens, and even off the lens altogether. This invention provides greater versatility in cutting a lens from a lens blank in a position that avoids peripheral irregularities i n the molded lens blank, while significantly decreasing tilt induced prism, yoked and vergence demands, and astigmatic blur along the line of sight and peripherally.
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